Question: Khan.scratchpad.disable(); For every level Christopher completes in his favorite game, he earns $670$ points. Christopher already has $330$ points in the game and wants to end up with at least $3570$ points before he goes to bed. What is the minimum number of complete levels that Christopher needs to complete to reach his goal?
Explanation: To solve this, let's set up an expression to show how many points Christopher will have after each level. Number of points $=$ $ $ Levels completed $\times$ Points per level $+$ Starting points Since Christopher wants to have at least $3570$ points before going to bed, we can set up an inequality. Number of points $\geq 3570$ Levels completed $\times$ Points per level $+$ Starting points $\geq 3570$ We are solving for the number of levels to be completed, so let the number of levels be represented by the variable $x$ We can now plug in: $x \cdot 670 + 330 \geq 3570$ $ x \cdot 670 \geq 3570 - 330 $ $ x \cdot 670 \geq 3240 $ $x \geq \dfrac{3240}{670} \approx 4.84$ Since Christopher won't get points unless he completes the entire level, we round $4.84$ up to $5$ Christopher must complete at least 5 levels.